Pipe-slotting machine



May 25 9 m6 C. J. COBERLY PIPE SLOTTING MACHINE Filed 001;. l, 1923 1-/1 Il i 1.

11 Sheets-'Sheet l ms/vivrai'.-

C/.AffA/cf J (05E/PL y TTONEMS:

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C. J. COBERLY PIPE SLOTTING MACHINE Filed oct. 1, 1923 11 sheets-she-a 2 IIII May 25 9 i926 C. J. COBERLY PIPE SLOTTING MACHINE Filed Oct. l, 1923 11 Sheets-She'et 3 Mfg/M A ATTORNEYS.

May 25 9 11926., 1,585,893

C. J. COBERLY PIPE SLOTTING MACHINE Filed OCC. l, 1923 l1 Sheets-Sheet 4' ATTORNEY@ May 25 9 1.926

C. J. COBERLY PIPE SLOTTING MACHINE Filed OCC. l, 1923 l1 Sheets-Sheet 5 a w n@ ,0o w) m a 4 4 i m Y 9 au 0 5 van E F 5 5 T /v w M 4 0 F a w J m /I M L M T ..11 5 fw m du K Q May 25 9 1926..

1,585,893 C. J. COBERLY PIPE SLOTTING MACHINE Filed Oct. l, 1923 l1 Sheets-Sheet 6 -IO I [ffm/FOR May 25 1926.

C. J. COBERLY P-IPE SLOTTING MACHINE Filed OCt. l, 1923 11 Shee'cS-She'eb 7 F' .IZ

May 25 1926B v 1,585,893

C. J. COBERLY PIPE SLOTTING MACHINE Filed Oct. 1, 1923 1l Sheets-Sheet 8 swf 35M ATTORNEK' May 25 ma. 1,585,893

C. J. COBERLY PIPE SLOTTING MACHINE Filed Oct. 1, 1923 1l Sheets-'Sheet 9 Aff/WOHNM May 25 H926., 1,585,893

' CJ. COBERLY PIPE -SLOTTINGr MACHINE Filed 061 1, 1923 v11 sheets-sheet 1o IV WMF.

fuhr/M+ May 25 1926.

c. J. COBERLY PIPE sLoTT'ING MACHINE Filed Oct. 1, 1923 1l heeizs-sl'xetV 11 Patented 'May 25, 1926.

UNITED -STATES CLARENCE J'. COBERLY, 0F LOS ANGELES, CALIFORNIA,

ASSIGNOR TO KOBE, INC., OF

LOS ANGELES, CALIFORNIA, A CORIORATION OF CALIFORNIA.

PIFE-SLOTTING MACHINE.

Application led October 1, 1923. Serial N'o. 665,917.

This invention relates to the art of cutting metals `by the use of oxygen, and relates particularly to a machine for cutting slots in pipe in such a manner that a Well strainer is thereby formed.

W hen a well has been completely drilled, it is customary to set a casing therein h aving a strainer at the bottom for excluding sand and gravel, but permitting the passage of liquids. Such strainers are often formed by perforating sections of easing which are placed at the bottom of the well, various means being employed to accomplish this perforation.

My invention provides a machine which, by the use of an arrangement of cutting torches, cuts elongated narrow perforations in the pipe. By the use of this machine, a perforation, narrow at the outer extremity and of increased width at the inner extremity so as to be self-clearing, and of consistent width throughout its length, is provided, thus converting the pipe into an ideal well strainer at a minimum expense.

It is an object of the invention to provide au automatically controlled machine having a movable support upon which an arrange ment of cutting torches may be adjusted in radial disposition relative to the pipe. A relative movement between the torch support and the pipe is provided so that the cutting action of the torch results in the formation of elongated perforations or slots.

It is a further object of the invention to provide means whereby the action of the torch is automatically controlled and correlated in such a manner that the combined i cutting action of the torches results in the formation of a series of uniform slots.

It is a further object of the invention to provide automatically controlled drills for perforating properly spaced holes in the pipe through which the cutting flame is directed at the start of' the cutting operation.

It is a further object of the invention to provide an exhaust means for removing the slag from the interior of the pipe being slotted, and means for cooling the slag in a manner to prevent its adherence to the inside of the pipe or the exhaust means.

It is a further object of the invention to provide a timing device for controlling the sequence of operation of the various niechanical elements incorporated in the machine.

It is a further object to provide in Con- ]unction with the timing device a means for checking the operation of the co-operative mechanisms. This checking means is arranged to shut down the machine in event that any one of the mechanisms fails to properly function or does not function in properly timed sequence.

Although the invention is described as bemg .particularly applied to a device for slotting pipe, it will be recognized hereinafter that the invention also incorporates a metal cutting machine employing a plurality of metal cutting torches and means for automatically controlling the torches so that they will be alike in cutting action. It is not. believed that at` the present time any device has been devised and employed in which a number of cutting torches are simultaneously employed, having correlated controlled mechanism whereby the action of the torches is synchronized. It is evident where a number of torches are to be employed simultaneously that such control is necessary if the device is to be operated by one attendant, as the adjustment of each torch, if separately connected, would require a considerable portion of an attendants time and would most likely make necessary the employment of a number of attendants.

The especial advantages of the invention and further objects thereof will be made evident hereinafter.

Referring to the drawings which are for illustrative purposes only,

Fig. l is a side elevation of a machine embodying the principles of my invention.

Fig. 2 is an elevation of the exhauster employed in conjunction with the cutting machine.

Fig. 3 is an enlarged fragmentary sectional view showing in detail the construction of the cooling spray head.

Fig. 4 is a section on a plane represented by the line 4-4 of Fig. 3.

Fig. 5 is an enlarged face view of the torch supporting member.

Fig. 6 is a. view showing the manner in which the drills are mounted upon the rearward face of the torch supporting member.

Fig. 7 is a vertical section showing the interior construction of one of the drills.

Fig. 8 is a plan view corresponding to Fig. 7. i

Fig. 9 is a front elevation of the drill.

Fig. 10 is a fragmentary section showing the manner in which the thrust bearings in the drill are placed for a reverse direction of rotation.

Fig. 1l is a. fragmentary partially Sectioned view showing the check switch employed on each drill.

Fig. 12 showstheindex mechanism employed for controlling the. movement of the pipe slotting face plate.

Fig. 13 is a partially sectioned view showing the index plate and the lead screw of the device.

Fig. 14 is a partially sectioned view to an enlarged scale showing the torch mounted on the torch support. l

Fig. 15 is a front elevation of the torch shown in Fig. 14.

Fig. 16 is a section taken on a plane represented by the line 16-16 of Fig. 14.

Fig. 17 is a sectional view showing thel type of valve employed in the oxygen and acetylene supply piping.

Fig. 18 is a vertically sectioned view showing the air valve which controls the feeding of air for the purpose of advancing the drill spindles.

Fig. 19 is a side elevation of the timing device.

Fig. 20 is a partially sectioned plan view thereof.

Fig. 21 is an end elevation of the device taken as indicated by the arrow 21 in Fig. 19.

Fig. 22 is a partially sectioned enlarged view showing the type of switch employed in the timing device.

Fig. 23 is an elevational view derived from Fig. 22, as indicated by the arrow 23.

Fig. 24 is a section taken upon a plane represented by the line 24-24 of Fig. 22.

Fig. 25 is a fragmentary sectional View taken upon a plane represented by the line .e5-25 of Fig. 22.

Fig. 26 is a wiring diagram illustrating schematically the arrangement and control of the mechanism incorporated in the slotting machine.

Fig. 27 is an enlarged fragmentary seetion of the diagram.

As shown principally in Fig. 1 of the drawing, the invention employs a bed 30 which is similar` in construction to the bed of a lathe, and which is provided with ways 3l upon which a carriage 32 is l slidable. Supported at one end of the bed 30 is a head 33 supporting a spindle 34 having a cone pulley 35, whereby it maybe driven from a motor 36 by means of a belt 37. Upon the rightward end of the spindle 34 is mounted an index plate 39 having concentric thereand stren th of the pipe.

with a chuck 40 which is preferably of universal type and is arranged to grip the end 41 of a length of pipe 42 placed in the machine for the purpose of being slotted. The

pipe may be supported by a steady rest 43,-

or other means suitable to the characteristics 0n the forward end 44 o the carriage 32 is mounted, by means of brackets 45, a torch supporting member 46 in the form yof an annular plate having T slots 47 and a comparatively large central opening 48 therein.

It is the function of the device, as hereinbefore explained, to cut slots in the pipe 42. This is accomplished by means of cuttingr torches 49, preferably of the Oxy-acetylene type, which torches are arranged radially upon the supporting member 46, as shown in Fig. 5. These cutting torches have the cutting nozzles thereof disposed inwardly so that when in operation they cut radial openings through the wall of the pipe 42. By providing a relative movement between pipe and the torches during the cutting action, it is possible to produce slots of anydesired length or extension. For example, by rotating the pipe through use of the motor 36, it is possible to cause the formation of circumferential slots in the pipe. By rotating the pipe and simultaneously advancing the carriage 32, helical slots may be obtained, and by merely moving the carriage while maintaining the pipe stationary, longitudinal slots are obtained.

In this description of the invention, explanation of the device in the production of longitudinal slots will receive our attention, it being understood that the other formation of slots may be readily accomplished by the use of known gear construction. For the purpose of advancing the carriage, a lead screw 51 is provided which is driven through a change gear box 53, gears 54 and belting 56 from the lead screw motor57.

When cutting metal by the use of an oxygen stream, it is customary to start to cut at the edge of the piece, this being due to the fact that when the starting of a cut is attempted within the plate, the flow of oxygen is obstructed by the metal and blows out wardly in a manner to form a hole of considerably greater diameter than the width which is ordinarily cut by the stream of oxygen delivered by the cutting torch. I have found that by drilling a small hole through the met-al at the point where the cut is to be started, the oxygen stream will be allowed to pass freely and the blowing out thereof around the sides will be eliminated, and a cut of uniform size obtained without the undesirable presence of the malformation now produced in the starting of a cut within the edges of a metal object.

In the slotting machine, I employ a number of drills 59 corresponding to the numlOO llO

ter of torches 49. These drills are mounted radially' upon the rearward face 60 of the supportlng member 46, as indicated in F ig. 6. These drills are provided with projecting pulleys 6l which are drivably engaged by a belt 62 which is driven by the drill motor 63 having a pulley 64. The general opfration of the device is substantially as folows:

A series of holes are first drilledat the plane indicated by 67, (see Fig. 1 these ioles being circumferentially spaced to correspond Witll the positions of the torches 49. T he torches are then.brought into alignment with the holes indicated at 67, whereupon the drills 59 operate and cause the drill bits 68 to drill a second series of holes in the pipe. The heat llames of the torches 49 are` then lighted, with the result that the metal surrounding the holes indicated at 67 is preheated, and when the proper temperature thereofl is reached, a cutting stream of oxygen is delivered from the nozzles 'of the torches, and the carriage through the action of the lead screw 51 is advanced in the direc tion indicated by the arrow 70, with the result that a longitudinal slot is formed. Upon reaching the end of the cut, the llow of oxygen is discontinued, but the advance of the carriage continues at this time until the nozzles of the torches 49 are brought into alignment with the second set of holes indicated at 71 in'Fig. 1. |The drills are then operated to drill'a succeeding set of holes and slots are then cut, starting with holes 71.

.In order to preserve a maximum strength in the pipe, it is desirable to oli'set the spacing ol the consecutive circular rows of slots. This is accomplished by partly rotating the pipe through rotation of the index plate 39 and chuck 40, by the motor 36.

Another feature ot' the invention consists of a means for relnoving the slag from the interior of the pipe 42, as the cutting action progresses. This means, as shown in Fig. 2, consists of a carriage 7 5 which travels upon a track 76, aligned with the movement of the carriage 32, and which is provided with `an exhaust fan 77 which communicates through piping 78 witha centrifugal sepa rator 79 having a door 80 in the lower end thereof. Extending forwardly from the separator' 79 is an exhaust nozzle 82 which consists preferably of a pipe of a diameter permitting its extension within the pipe 42. Dueto the action of the fan v77, a strong suction is created within the pipe S2, with the result that air is drawn into the nozzle Ias indicated by the arrows in Fig.

86, avk plate is mounted, this plate beingl are readily adapted to use therewith, by ini creasing the diameter of the members 90 and 9.1. Water is supplied to' the spray head 86 by a pump-93 which, through a pipe 94, draws water from a sump 95 which is in the form ofa ditch disposed between the tracks 76 so that it will be under the carriage 75. Through a link 96 the carriage 75 is moved with the carriage 32, thus causing the mouth of the exhaust nozzle to be maintained in alignment with the cutting torches. In view of the fact that the pipe 42 does not travel axially, it is necessary for theI exhaust nezzle to move axially therewithin. 'l`l1ercl' n'e, slides 99 (see Figs. 4 and 6) arc provided near the forward end of the nozzle, these slides 99 resting on the interior of the pipe 42 and sliding therealong as the exhaust nozzle advances. For the purpose ot supporting the spray pipe 85 within the pipe 82, any desirable means such as the radial arms 100 may be employed.

As shown in Figs. 7, 8 and 9, each drill unit 59 includes a casting 102 arranged to slide along a radial plate 59a and be clamped in adjusted position thereon by a T bolt 106 engaging into a-T-slot 106a in said plate.. The several plates 59a are secured to the rearward face 60 of the support 46 by T- bolts 60b (indicated in Figs. (Sand 8) engaging in concentric T-Slots (50a formed in said rearward face 60. By this arrangement the several plates 59*1 may be relatively spaced circularly and clamped in radial alignment with the work, and subsequently the individual drillunits may each be adjusted radially upon its separate plate 59a. Inthe upper portion of each casting 102 a cylinder 103 is formed in which there operates a piston 104. Downwardly extending from the piston 104 is a spindle 107 which at its lower end carries a drill bit 68. The spindle is normally held in upward position by a spring but is caused to advance downwardly when air or other Huid is introduced through an opening 111 into the upper end of the cylinder 103. The spindle 107 is splined through a rotary sleeve 113 which may be mounted in self-aligning ball bearings 114 and is driven from the pulley 61 through a worm gear 115 and a worm wheel116.

From an inspection of Fig. 6, 'it will be of pipe being 'the thrust of the worm and wheel ron the sleeve is applied either upwardly or down- 'wardly, depending upon the`direction ofv rotation of the worm. In Fig. 7, a thrust b earing 118 is shown for receiving the down- 'ward'thrust of the s lceve 113. In Fig. 10, a thrust bearing 119 is `shown in a position to receive an upward thrust ot' the sleeve 113. In, the construction employed, a slight change in the installation of the thrust bearing equips the drill for either right or left hand rotation of the pulley. The travel of the spindle and the raised -position of the drill bit 68 will naturally vary with the diameter and thickness of pipe employed in the slotting machine. For adjusting vthe outward travel ofthe spindle '107, an adjustment screw 122 is provided at the upper end of the casting 102, and' for supporting the drill bit 68, a vertically movable post 123 is provided having a rearward-ly extending arm 124 inwhich a hardened steel bushing 125 is held for guiding Ithe drill 68. The number and spacing of the drill units 59 is arranged in accordance with the diameter of the pipe, and'thenumber of torches em ployed.

The construction of the torches is shown in Figs. 14, 15 and 16, Fig. 14 being a section taken substantially as indicated by the line 14 of Fig. 5. The torches 49, as indicated in Fig. 14, are of standard construction eX- c'ept for the fact that the nozzle heads 135 thereof are of special form and a-replaced in close relationship to the control head 136. A particulartype ot bracket 137 lis employed for mounting the torch on the slotted member 46, this bracket consistingprinci'- pally of a post 138 which is secured to the :Face of the member 46 by means of a T bolt 139 which extends through the post 138 and has a nut 140 on the outer end thereof. Silding upon the member 138 is a sleeve142 which may be clamped in any position along the post 138 by means of a clamping bolt 143, or maybe rotated thereon. Upon .a cylindrical projection 145, formed upon the sleeve 142, a second clamping sleeve 146 is mounted, this sleeve being arranged to receive the barrel 148 of the torch -49 and 'being provided with aclamping bolt 150. rIfhe peculiar constructionof these .brackets enables the torches -to bek clamped in any direction of extension. f 'y f Oxygen is delivered to thev torches 49 through la header havin outlets 156 and a feeder 157, throughwhich Vfeeder the header receives the oxygen gas, this feeder 157 being provided with a valve A158 of special construction, which will hereinafter be described. The acetylene is delivered to the torches through a header 160 which is fed by a feederll having aspecially constructed valve 162. As' lshown in Fig. 5, water delivery and takeoii pipes and 166 are provided or the purpose of delivering cooling water to the jackets 167, Fig. 14, which enclose the torch nozzles 168. These water jackets'are interconnected through pipes 169 and coupling tubes .171 so that a continuous flow of water is directed through the consecutive water jackets' and the overheating of the cutting tips 168 is thus prevented. As also shown in Fig. 14, pilots 17 0 are provided for the purpose of directing a. small pilot iame 172 -adjacent'to each nozzle, so that the torches will be kept lighted and will be relighted in case of any backfire. y

' In Fig. 26 is diagrammatically represented the electrical control of the equipment and the various mechanisms thereof. Power for operating is derived originally from a three phase alternating circuit consisting of wires 460, 461 and 462, from which the spindle motor 36, the .lead screw motor 57 and the drill motor 63 aresupplied with electrical energy through separate sets of wires in which three pole switches 463,464 and 465 are placed.

For the purpose of controlling and checking the action of the various parts, direct current is generated by a generator 467 driven yby a three phase motor 468, fed from the three phase circuit through wiring 469, and a three pole switch 470. The generator 467 feeds a .main line consisting of the separate mechanism indicated in the dia- I gram. The switches a, b, 0, and g are a part of the timing device shown in Figs. 19, 2O and 21, which comprises essentially a base upon which a horizontal shaft 181 supported in journals 182 is held in driven relationship through a system of reducing gears 183 with the mot-or 184. The reducing gear arrangement consists essentially of a worm 186 which is mounted on the shaft 187 of the motor, which worm engages a worm wheel '188 which drives a gear 190. From the gear 190 a gear 191 is driven through a remove' able speed ratio `changing idler' 192. The gear 191is mounted upon a shaft 492 which has ke ed thereon a worm 193, Fig. 20, which rives a worm wheel 194 mounted'on a sha-ft 181. On the shaft 181 discs or yrotors 195 are placed and are rigidly secured llO the cams 208 in which it is preferable to provide four pockets 210 so that the cam wlll )e rotated through an angular distance of 90 degrees at each engagement therewith by a tooth member 200.

Adjacent to each of the cams 208 is placed a switch member 215 which is shown in detail in Figs. 22 to 25.l Each switch member 215 comprises a vertical post 216 which may be supported on the base 180 by means of the angle'member 217 and machine screws 218. Upon the front of the post 216 a central spring contact member 220 is placed which has a dog 221 at the upper end thereof, arranged to beengaged by the cam projections 222. `Between the member 220 and the post 216, a pair of flat spring members 225 and 226 are mounted, while in front of the member 220 a single contact spring 227 is mounted, all of the members 220, 225, 226 and 227 being supported between insulating plates 229 and by insulated bushings 231 and secured to the post 21.6 by bolts 230. It is convenient to provide an opening 232 beneath the lower ends of the spring contact members to which interconnecting wires may be soldered, as shown at 233 in Fig. 22.

In Fig. 25 a contact point 235 is shown upon the member 225, which contact member is arranged for engagement by a contact member 236 secured upon the rearward face of the spring 220. The spring member 226 is provided with a contact point 237 arranged for engagement by a point 238, which is also mounted on the spring 220. It will be noticed that the space between the pairs of contact po-ints 235, 236, 237 and 238 is not the same and therefore when the spring member 220 is moved in the direction of the arrow 240 in Figs. 22 and 25, contact will be made between the points 235 and 236 before the` contact members 237 and 238 come together. As shown in Fig. 22, a contact point 241 is mounted on the front side of the spring 220, which is arranged to engage a cont-.ict 242 mounted on the spring 227. The contacts 235 and 236 `constitute a control switch, or in other words one of the switches designated in Fig. 26 as a, b, 0, etc. The switches formed by the pairs of contacts 237-238, and' 241-242 are checking switches and form part of the means for checking the operation of the specific mechanism with which they are associated.

The cam operating members 200 are mounted upon the rotors 195 in position to engage and rotate the cams 208 in proper sequence. The rotation of the members 195 is in the direction of the arrow 250 of Fig. 21, which therefore would cause a rotation ot' the cam 208, Fig. 22, in the direction of the arrow 251. As' the cam is rotated through its quarter revolution, the sloping approach 252 to the projection 222 forces the dog 221 rearwardly, with the result that contact is made between the points 235 and 236 and contact between the points 241 and 242 is broken. Shortly afterward when the dog 221 is brought nearer the outer face of the cam projection 222, the contact points 237 and 238 are brought together, thus closing one of the checking switches.

For an example of the operation of a control switch and checking switch system, Fig. 27 may be considered in conjunction with Figs. 14 and 22. The oxygen valve 259, Fig. 14, controlling the delivery of the cutting stream of oxygen is operated by an armature 260 impelled by a solenoid 261. On the rearward end of the armature 260 is a projection 263 which engages two spring members 264, having contacts 265 and 266 disposed at the upper end thereof. When the solenoid 261 is not energized and the` armature 260 is Iheld back by the spring 262 in the position shown in Fig. 14, the. contact point 266 will rest in engagement Iwith the point 267. When the armature is impelled forwardly in order to open the valve 259, the contact member 264 will spring forwardly, allowing the point 265 to rest against a point 268. The solenoid 261 is represented in the fragmentary diagram, Figa 27. and the contact points 265, 266,

267 and 268 are also'represented therein. The Contact points 265 and 266are connected to the line wire 176 through conductor means 270 and the contact points 267 and 268 are respectively connected by wires 271 and 272 with the contact points 237 and 241 of the timing switch member sho-wn in Fig. 22. The contact members 242 and 238 of the switch 115 communicate with a parallel line wire 275 which leads to a solenoid trip 276 arranged to open the switch 1.77 when electrical energy is passed therethrough. It will be seen that in event of contacts 242-241 and 268-265 being in engagement at one time, electrical energy would flow through the conductors 176 and 275 withv the result that the entire system would be shut down.

Let it be considered that the cam projection 222, Fig. 22, is not in engage-ment with the dog 221. .At this time the spring member 220 will rest in outward position with contact between the points 235-236 and 237-238 broken, and the switch comprised of the points 241 and 242 closed. Owing to the fact that the contact members 235 and 236 are separated, the solenoid 261, Fig. 14, will rest in a position to hold back the member 264, which results in the contacts 265 and 268 being opened and the contacts `266 and 267 being closed. Therefore, no current will How between the conductors 176 and 275; but suppose that the armature at this time were stuck in forward position, the contact points 268 and 265 would then be in engagement and a closed path through I the conductors 270,272 and 280 would be! provided with the result-f the actuation of the trip solenoid 276. v

When engagement of a cam operating projection 200 causes the rotation of the ther rearward .movement of the spring member 220 under pressure of the cam, contact will be made between the points 237 and 238. If at the time this Contact is made, the contact between the points 266 and 267 has not been broken due tothe failure of the solenoid 261 to force the core 260 inwardly, current will flow between the conductois 176 and 275 with the result of l shutting down the system.

In this manner an automatic check is at all times maintained on each mechanism of the machine, so that in event one element fails to roperly operate, the machine will be shut own and an annunciator having an electromagnet 270a is operated, thus notifying the attendant that something is wrong.

At the drop off 290, Fig. 22, of the camy projections 222,' a slight slope is provided in order to provide a space of time between the opening of the contacts 235--236 and 237-238 and of the closing'of the contacts 241 and 242, thus allowing ample time for the core 260 to return to the position in spring-318,? tiret-valve will which it will holdl the conta-ct points 265 and 268 out of engagement. The checking switch arrangement ma be designated as sets of switches X and shown in Fig. 27. Therefore in Fig. 26, each of the control` switches a, b, c, and g ma be shown with checking switches X and F where such use is necessary, the use thereof being indicated on the spindle index solenoid 3 00, Fig. 12, the lead screw index solenoid'` 301, Fig. 13, and the .air valve solenoid 337 for the drills indicated Ain Fig. 18.4

1n Fig."17 the valve mechanism for controlling .the deliver of oxygen to the flames in the cutting tore es is shown. The position of this valve is indicated by 158 in Fig. 5. -A member 310 is provided with an inlet 311 and an outlet 312, whichv communicate with a vertically.. drilled4 opening". 313, in

317 downwardly-against is kraised into a forcing of the Yvalve is accomplished by valve indicated at 162 in Fig. 5, is of sub' stantially the same construction as-the oxygen valve, with the exception that the piston and cylinder speed control is omitted, allowing the valve to snap open or closed. By this arrangement I am enabled to provide a lag in the closing and openin of the oxygen valve, thus permitting the acetylene flame to be lighted before thev appearance of oxygen and allowing the acetylene to be shut off before the closing off ofthe oxy en which is desirable as it prevents formation of carbon in and on the torch tip.

The air valve indicated at 326, Fig. 6, con-v trols the flow of air into the air header from which the leads 327 (see Fig. 7) are taken to the separate cylinders 103 ofA the drill units 59. This air valve shown in Fig. 18 provides a block 330 having an inlet 331 and outlets 332 and 333. Through a needle valve 334 air is directed into the inlet 331 and may flow through the outlet 332 when the Valve member 336 is depressed by the action of the solenoid 337 on the armature 338. When the member 336 is forced downwardly, its valve member 340 is removed from engagement with the valve cooperating seat and lts valve member 341 is brought into a position to close and prevent the passage of air through the opemng 333. The rate of flow of the air is controlled by the needle valve V334, therefore determining the rate of speed at which the drill spindles will ad- Vance or, in other wordsZ regulating the rate of feed of the drill bits into the metal walls of the pipe. after the hole has been'drilled is, however, not retarded, as the air may flow freely from the opening 333 when the valve member 336 position to close the valve 340.

A valve similar to the one just described may be employed at 350 in Fig. 6 to control the delivery of air through a header 351, which feeds the air nozzles 352 employed for coolingand lubricating the drillbits during their cuttingoperation. An oil atomizer 354 may be employed in conjunction' with the rheader 35.1, whereby fine particles of atomized oil may for the'purposeof lubrication. F or" tlejpur The return of the spindlesy y be intermixed withth'e. streamofalr a-nd'thusl carried to theIdij'llj' wheel when the members 405 and 406 moveV pose of holding the spindle 34 and the lead screw 51 in proper inde.\ed position, the solenoids 300 and 301, Figs. 1 and 5, are employed. The armature 380 of the solenoid 300 supports a pin 381, which is arranged to engage openings 382 in the face plate 39, which is supported upon the spindle 34, and an index plate 385 is provided u on the rearward end of the leadfscrew wiich is provided with openings 386 arranged for engagement by a pin 387. The pins 381 and 3.87 are applied and released in proper sequence through the action of the timingI device which will be readily understood from the diagram, Fig. 26.

The check circuit for checking the action of the drills 59 differs in regard to the uumber of contacts employed and is merely a single contact arrangen'xent instead of a dou-' ble or multiple arrangement, indicated at X and Y. 0n the post 123, Fig. 7, the checking switch 400 is mounted, the details of which are shown in Fig. 11. In a hollow body 401 a ratchet 402, associated with a cam member 403, is mounted in a position suitable for engagement by pawls 404 supported by a member having outwardly extending fingers 405 and 406. It w-ill be noticed that there are two teeth in th'e ratchet 402 for every projection 407 of the cam member 403, therefore, it is necessary for two teeth of the ratchet 402 to be advanced in order to bring a projection `407 into engagement and then out of engagement. The cam projections 407 are arranged to force a spring member 409 rearwardly so as to separate the' contact points O and P. The members 405 andl 406 may be conveniently an integrall structure and the actuating pawl 404 arranged to engagey and rotate the ratchet outwardly after being depressed. A The operation of the device is substantially as follows:

lVhen the spindle 107 is in raised position, the cap 410 on the lower end thereof is in engagement with the member 405 and holds the same in depressed position as shown. At this time the air valve 325, controlling the flow of air to the cylinder, and the contact points 241 and 242 of the controlling switch, connected to the drill motor, are in closed position and the drill mot-or is not in operation. When the cam 208 isv rotated for the purpose of starting the drill motor, the control switch f, consisting of the contact points 235 and 236, is closed and at this time the contact points 241 and 242 are separated. The drill spindle then moves downwardly and the cap 410, FigQll, moves out of position in front of the finger 405, allowing it to move outwardly under the action of the spring 415 with the result that the pawl 404 moves the vratchet 402 one tooth, thus bringing the cam 407 out of engage-ment with the membcr400 lso that the switch con- I tact at this time becomes closed. lower end of the spindle travel the cap 410 At the engages the linger 406 and forces it inward y ly with the result that the )awl 404 is brought into a. position in Whic 1 it will engage a succeeding tooth of the ratchet 402. There can, however, be no movement of the pawl in an outward direction to cause the turning of the ratchet wheel 402 until the spindle has started upwardly and has cleared the finger 406 so as to allow it to 406 will be maintained in depressed position therefore causing the contact points O and l to remain closed, with the result that, 'upon the opening ot the switch g and the closing of the contact points 241 and242, a circuit would be formed between the line wires 176 and 275 through the closed contacts O and P and the closed contacts 241 and t242, thus causing the operation `of the solenoid trip 276 with the result of opening the switch 177.

As a safety factor a no voltage release 450 is provided for tripping 4the switch 1-77 in case the three phase feeding circuit, consisting of the conductors 460, 461 and 462, should be shut otf for any reason. The spindle motor 36, the lead screw motor 57, and the timing mechanism motor 184 are respectively provided with solenoid brakes 430, 431 and 432, Figs. l and 2O which are electrically connected in circuit with the motors in such a manner that the brakes will be applied when the current is discontinued. In making adjustments in the setting up of the machme for the slotting of a certain size pipe, the spindle 34 must be manually rotated. Therefore, it is desirous to provide a lever 440, Fig. 1, which will operate a cam 441 in a manner to separate the brake memb'ers of the solenoid brakerso that the motor may be turned manually when the propelling current is off. c

The timing device is so constructed as to provide a marked flexibility in adjustment.

The speed at which the shaft 181 is driven may be accomplished by inserting' additional toothed members 200 to ive the desired repetition of operation of tlfie drills.

I claim as my invention: c

1. In a pipe slotting machine, the combination of: means for holding a pipe;'a plurality of relatively spaced cutting torches disposed eziteriorlyl of and radiallyA with respect to said pipe with the nozzles thereof ,spaced in cutting arrangement relative thereto;imeans for supporting said torches in circular disposition around the pipe; andmeans for roducing a relative movement between sald supporting means and said pipe.

2. Ina pipe slotting machine, the combiplurality of cutting torches disposed around 1 said pipe in relatively spaced substantially -v radial positions; and carriage means for `s'upportin said torches sothat they may be carried re atively along said pipe.-

" 4. In a pipe slotting machine, the combifnation of: means for holding a pipe; a plurality of cutting torches disposed around saidp'ipe in relatively spaced substantially ,.iadial positions; and means, movable relative to said pipe sup'portmg means, for supi porting said torches 1n such a manner that they may be moved relatively along said pipe.

5.7"111 a pipe slotting machine, the combifnation of: means for holding a pipe; a plurality of relatively spaced cutting torches disposed radially in cutting position with 'respect-to said pipe; means for su porting said- `tor`ches; and means for pro ucing a relative.movement between said pipe and said torches so that the cutting action of i. saidrtorchesv will produce slots in said pipe.

6. 'In a pipe slotting machine, the combii nation oft' means for holding a pipe; a plurality of relatively spaced cutting torches disposed radially in cutting position with respect to said pipe; means for supporting said torches; means for producing a relative movementlbetween said pipe and said torches so that the cutting action of said torches will produce slots in said pipe; and means for timing said movement for the purpose of producing slots of a definite length.

7. In a pipe slotting machine, the combination of: means for holding a pipe.; torches disposed in cutting position with respect to said means for supporting said torches; means for producing a relative move- Iment between said pipe and said torches so that the cutting action of saidvtorches will produce slots in said pipe; means for mechanically forming holes at the points where said slots are to begin, through which holes the flames from said ltorches pass when starting their respective cuts; and means for timing said movement for the purpose of producing slot's of a delinite length;

8. In a pipe slotting machine, the combination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; means for supporting said torches; means for producing a' relative movement between said pipe and said torches so that the cutting action of said torches will .produce slots in said pipe; and means for mechanically forming holes at the points where said slots are to begin, through which holes the flame from-said torches pass when starting their respective cuts.

9. In a pipe slotting machine, the combination of: means for holding a pipe; torches disposed lin cutting position with respect to said pipe; means for supporting said torches; means for producing a relative 'movement between said pipe and said torches so that the cutting action of said/torches will produce slots in said pipe; and an exhauster for drawing the slag from said pipe..

10. In a pipe slotting machine, the combination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; means for supporting said torches; means. r for producing a relative movement between said pipe and said torches so that the cutting action of said torches will i produce slots in said pipe; an exhauster for drawing the slag from said pipe; and means for introducing a spray of cooling liquid for the purpose of cooling said slag. y

11. In a pipe slotting machine, the combination of; means for holding a pipe; torches disposed `in cutting position with respect to said pipe; means for supporting said torches; means for producing a relative move- Vment between said pipe and said torches so that the cutting action of said torches* will roduce slots in said pipe; an exhauster for rawing the slag from said pipe; and means for introducing aspray of cooling liquid in the form of a spray at the mouth of said exhauster for the purpose of cooling said slag.

12. In a pipe slotting machine, the combination of: means for holding a pipe;

torches disposed in cutting position with respect to said pipe; means for supporting said torche/s; means for producing a relative movement between said pipe and said torches so that the cutting action of said torches will produce slots in said pipe;

and an exhauster consisting of an exhaust nozzle arranged to extend within said pipe and exhaust means producing a draft through said nozzle for drawing the slag from said pipe.

13. In a pipe-slotting machine, the coinbination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; means for supporting said torches; means for producing a relative movement between said pipe an-d said torches so that the cutting action of said torches will produce slots in said pipe; and an exhauster consisting of an exhaust nozzle, a carriage supporting one end of said nozzle, a collector at the end of said nozzle, and an exhaust fan for drawing a draft of air through said nozzle for drawing the slag from said pipe.

lll. ln a pipe slotting machine2 the combination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; means for supporting 'f said torches; means for producing a relative movement between said pipe and -said torches so that the cutting action of said torches will produce slots in said pipe; an exhauster consisting of an exhaust nozzle arranged to extend within said pipe and exhaust means producing a draft through said nozzle for drawing the slag from said pipe; a spray head at the mouth of said nozzle for emitting a spray of cooling fluid for cooling the slag produced by the cutting action of said torches on the metal of said pipe; and means for supplying said cooling fluid to said spray head.

15. In a pipe slotting machine, the combination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; meansr for supporting said torches; means for producing a relative movement between said pipe and said torches so that the cutting action of said torches will produce slots in said pipe; an exhauster consisting of an exhauster nozzle arranged to extend within said pipe, and exhaust means producing a draft through said nozzle for drawing the slag from said pipe; a spray head at the mouth of said nozzle for emitting a spray of cooling iuid for cooling the slag produced by the cutting action of said torches on the metal of said pipe, said spray head being of substantially the same diameter as said nozzle and being spaced away from the mouth of said nozzle to provide an annular opening therebetween; and means for supplying said cooling fluid to said spray head.

16. In a pipe slotting machine, the combination of: means for holding a pipe; torches disposed in cutting position with respect to said pipe; means for supporting said torches; means for producing a relative movement between said pipe and said torches so that the cutting action of said torches will produce slots in said pipe; an exhauster consistin of an exhauster nozzle arranged to exten within said pipe and exhaust means roducing a draft through said nozzle for drawing the slag from said pipe; a spray head at the mouth of said nozzle for emitting a spray of'cooling iuid for cooling the slag produced by the cuttin action of said torches on the metal of sai pipe, said spray head being of substantially the same diameter as said nozzle and being spaced away from the mouth of said nozzle to provide an annular opening therebetween; and means for supplying said lcooling fluid to said spray head,'comprising essentially a force pump and duct means communicatin between said pump and said spray hea 1f?. In a pipe slottin machine, the combinationof: means for iolding a pipe; cutting and feeding mechanisms cooperating in a manner to produce slots in said pipe; a power drive and checking means arranged to render all' of said mechanisms inoperative on failure of one of said mechanisms to properly function, said checking means comprising a device operating in vunison with all of said mechanisms and functioning to throw out the power drive with an interruption in the normal sequence of operation of the several mechanisms.

18. In a pipe slot-ting machine, the combination of: means for holding a pipe; cutting and feeding mechanisms cooperating in a manner to produceslots in said pipe, a timing device controlling the sequence of operation of said mechanisms; a power drive and checkin means arranged to render all of said mec anisms inoperative on failure of one of said mechanisms to properly function, said checking means comprising a device operating in unison with all of said mechanisms and functioning to throw out the power drive with an interruption in the normal sequence of operation of the several mechanisms.

19. In a machine for performing a series of operations on an article, the combination of: means` for holding the article; mechanisins cooperating in performance of a series of operations on said article.; -a power drive; timing means controlling the sequence of operation of said mechanisms; and means associated with said timing means for rendering all of s-aid mechanisms inoperative when any one of said'mechanisms fails to properly function, said last named means comprisin a device operating in unison with all o said mechanisms and functioning to throw out the power drive with an interruption in the normal sequence of operation of the several mechanisms.

20. In a machine for performing a series of operations on an article, the combination 

